Manufacture of building-blocks or the like.



PATENTED MAY 16, 1905. CAMPBELL.

G MANUFACTURE OF BUILDING BLQOKS OR THE LIKE.

APPLICATION IILIHD JUNE 7, 1904.

Wadi-asses Mu d. C.

UNITED STATES Patented May 16, 1905.

PATENT OFFICE.

GEORGE PLUMMER CAMPBELL, OE FRESHFIELD, ENGLAND, ASSIGNOR TO THE HYDRAULIC BRICK AND STONE COMPANY LIMITED, OF LIVER- POOL, ENGLAND.

MANUFACTURE OF BUILDING-BLOCKS OR THE LIKE.

SPECIFICATION forming part of Letters Patent No. 790,183, dated May 16, 1905.

7 Application filed June 7, 1904. Serial No. 211,539.

' To all whom it may concern.-

Be it known that I, G EORGE PLUMMER CAMP- BELL, a subject of the King of England, and a I resident of Freshfield, in the county of Lan: caster, England, haveinvented certain new and useful Improvements in or Connected with the Manufacture of Building-Blocks or the Like, of which the following is a specification.

This invention has reference to the manul0 facture of artificial stone or hollow building blocks used in buildings; and the object of the present invention is to produce hollow buildingblocks quicker and more cheaply than they have hitherto been made and to produce in such blocks a better resemblance to natural building-stone than heretofore.

According to this invention the hollow building-blocks are made of lime and sand placed in a mold of the external form and shape of block required and with a central core or cores. The lime is slaked and is thoroughly mixed with the sand and then filled into the mold and subjected to pressure, after which the hollow block thus made is removed from the mold and subjected to the action of highpressure steam in a closed chamber for about ten hours. After this the block is ready for use. A number of these blocks may be placed on wagons or vehicles and treated with steam in large quantities in closed hardening-chambers in the manner referred to.

In the case of blocks requiring carved or irregular surfaces the sides or ends, or both, of the mold are so made that they may be readily removed or detached or pulled and.

taken away from around the finished block before it goes into the hardening-chamber.

According to a slightly-modified mode of manufacture of hollow building-blocks of lime 4 and sand unslaked lime and sand are mixed and ground to a fine powder, and this powder in its dry state is filled and pressed into the mold, with a central core for forming the hollow in the block. In this case the closed molds, with their contents of lime and sand,

are placed upon wagons and run into achamher which is then closed up tight and is then filled with water, so as to cover the molds and slake the lime, the water being heated by steam or other heat and kept hot for several hours. The water is then run off and the blocks and molds are subjected to high-pressure steam in the place of the water. This completes the hardening of the blocks, and they are then removed from the chamber and taken from their molds and the cores removed, when they are ready for use.

To obviate an excess of lime being in the blocks and to render them of the highest quality, pozzuolana or trass may be added to the mixture of lime and sand, these materials being kept in a hot state in a mixing-machine. By this addition the faces of the hollow blocks when finished do not have cracks in them.

One form of construction of mold suitable for manufacture of hollow blocks under this invention, and more particularly to the process lirstdescribed, is illustrated in the annexed drawings, in which Figure 1 is a sectional elevation through the mold box and core, and Fig. 2 is a plan with the top plate removed.

Referring to the drawings, a represents the two side plates of the mold; t, the two end plates; 0, the bottom plate, and d the top plate or cover.

6 is a thin bottom plate which rests upon the plate 0, the latter plate being held and pressed up by the ram f of, say, a hydraulic press.

The core consists of a wedge-shaped central piece g and two end pieces it, between which the piece g fits, and the core at its upper end projects through a slot in the cover d.

The sides a are fastened to the ends 5 by studs or bolts and nuts 2', and the cover (.Z is fastened to the ends I) by studs or bolts 7'.

In using the apparatus the top plateorcover (Z is removed and the carrier-plate e placed on the bottom follower or presser-plate c of the press or mold, and upon this plate 0 the cores it are placed in the right position. The mold-box is then filled with the mixture, and the top plate or cover 0? is put in place and screwed down tight by the screws or bolts and nuts j. The follower or presser-plate c is then forced up by the presser-ram, and thus compresses the material or mixture witl in the mold, and as the plate 0 rises the core 9 7L will rise up through the opening in the cover or plate (Z, in which it forms a sliding fit. When the mixture is sufficiently compressed, the core 9 h is drawn up out of the block through the aperture in the cover (Z, and the cover is then taken off. The sides a and ends 6 are then taken apart, thus leaving the hollow block resting on the carrier-plate e, and this plate with the block on it is then taken from the presser-plate c and placed on a wagon or the like for removal to the harcloning-chamber, as above described. A fresh carrier-plate is then put on the follower or bottom of plate 0, and the sides (a and ends 5 are again put together and fastened, and the mold is then ready for making another block.

In the case of making hollow blocks from unslaked lime and sand, as referred to in the modification of the process, the bottom of the mold will be ridged and permanentlyattached t0 the mold sides, and the mold with its contents is put into the hardening-chain]l er, treated as described, the necessary compression in this case being obtained by the expansion of the lime during the slaking.

Having now particularly described my invention, What I claim as new, and desire to secure by Letters Patent, is-

In the manufacture of hollow or artificial stone made of lime and sand, a mold comprising detachable sides (0, ends 7), a cover j, movable bottom a, and a core it in the center of the mold, fitting in and adapted to project through and slide in the cover j, and adapted to rest and be pressed upon by the bottom 0; substantially as set forth.

In witness whereof I. have hereunto set my hand in presence of two witnesses.

GEORGE lliUillMlllt CrUlllillhb.

Vitnesses:

S. GOODALL, G. OKE. 

